(a) Field of the Invention
The invention relates to a land grid array connector, and more particularly, to a land grid array connector having high-density contact points serving as connecting structures between a circuit board and another circuit board, or between an integrated circuit and a circuit board. The land grid array connector is deformed when a signal transmission portion thereof is suppressed without resulting in permanent deformation, however. Wiping movements of the contact points are performed between a circuit board and another circuit board, or between a circuit board and an integrated circuit, so as to remove oxidized thin-films at involved contact surfaces for facilitating signal transmission. Moreover, when terminals of the connector are assembled to corresponding terminal grooves at a connector plastic housing, a gap is reserved between the terminals and rear walls of the terminal grooves, and is for absorbing variation caused from suppression of a signal transmission portion, thereby accomplishing optimal connection effects.
(a) Description of the Prior Art
A common land grid array connector, and especially a high-density connector as disclosed by the U.S. Pat. No. 6,062,871, 6,146,152, and 6,203,331 (FIG. 8 shows the U.S. Pat. No. 6,062,871), comprises an insulative housing 10 having a plurality of slits 11, and a plurality of terminals 20 with a pair of contact points and being inserted in the slits 11. Each terminal 20 is a structure directly formed from a metal plate by stamping, wherein a first contact point 21 thereof is extended upward from a transmission section 23 thereof, and a second contact point 22 is disposed at a bottom end of the transmission section 23. Therefore, the material anti-bending strength (flexibility) between the upper and lower contact points 21 and 22 is a square of a width of cross section multiplied by a height of the upper and lower contact points 21 and 22. The contact points are limited by the transmission section 23 of the terminal 20, and variation thereof is not drastically fluctuated due to limitations of space. Although a cantilever in a middle section receives a portion of stress, stress imposed on the terminal 20 is yet quite large due to the limited variation. In addition, stress is amplified by the plurality of terminals 20 in the entire connector. Consequently, when the connector is applied in a land grid array connection with unsatisfactory planeness between individual contact points, a portion of the terminals may have poor contact. To provide the terminals with better contact, large forces pressing downward are needed. However, deformation of the circuit board then becomes probable and again leads to poor contact, or even damages of components therein.
It is observed that the terminals of the prior land grid array connectors have crucial influences over connection effects, and drawbacks as being likely to damage components and thus increase production costs. Therefore, it is a vital task of the invention as how to advance the prior invention, so as to provide good contact effects, and overcome the above drawbacks namely being likely to damage connected circuit boards or electronic components.